1. Field of the Invention
The present invention relates to a plot planter. More specifically it relates to a plot planter which uses two finger pickup units to enable precise control of both the beginning and end of rows of seeds of different types.
2. Description of the Prior Art
The use of plot planters for the use of research is widely used in the seed industry. In a research plot it is necessary to plant several different seed types in one field for the purpose of obtaining yield and growth data. These plot planters are responsible for planting seeds of uniform spacing, in a row of a predetermined length, one variety right after another. A variety of plot planters are known in the art. Examples of some of such known devices are shown in U.S. Pat. Nos. 6,626,120; 6,564,730; 6,401,638; 6,374,759; 6,325,005; 6,109,193; 5,542,364; 5,392,707; 4,896,616 and 4,285,444. The prior art plot planters use complicated mechanisms and electronics. While they have many features for closed loop monitoring of the planting, they are intimidating and even the simplest of problems can be hard to fix. Another problem with the prior art is the seed metering devise. Many plot planters are using air metering devises and cone metering devises. They do not respond well to rough field conditions. The seed distribution can be compromised from bumps in the field that shake the plot planter.
It is therefore the primary objective of the present invention to solve the problems identified in the prior art.
Another important objective of the present invention is to provide an affordable method of seed metering.
Another object of the present invention is to provide a seed metering device that is not overly complex, while maintaining the reliability and accuracy required in the art.
Another objective of the present invention is to provide a seed metering device that is easy to maintain and not prone to frequent break-downs.
Additional objectives and advantages will become apparent by those skilled in the art in the accompanying specification.
The present invention provides an accurate seed metering device using a simple industry-standard finger pickup unit. The invention uses two finger pickup units per row because the finger pickup unit is repeatable when it begins planting, but it isn""t repeatable when it stops planting. This problem is overcome by using two finger pickup units per row. To control which unit plants, there are two grain valves: one positioned above the finger pickup units, and one below. These valves work together to control the alternation of which finger pickup unit is planting.
The present invention solves the problem of the prior art devices by utilizing a simple seed metering device and eliminating the complexity of wires, computers, and hydraulics. The finger pickup units solve the problem of compromised seed distribution in rough fields. The finger pickup unit itself is designed to hold the individual seed in place as it isolates it from the rest of the seeds. This reduces the chances of a bump in the field effecting the distribution.
In its simplest form, the present invention provides a plot planter comprising: a top valve including a sliding block movable between a first block position and a second block position, said sliding block having a first seed chamber adapted to receive a first type of seed and a second seed chamber adapted to receive a second type of seed; a first finger pickup unit communicating with said first seed chamber when said sliding block is in said first position and a second finger pickup unit communicating with said second seed chamber when said sliding block is in said second position; a bottom valve having a first position allowing seed from said first pickup unit to be delivered to a seed tube for planting while collecting seed from the second finger pickup unit, said bottom valve having a second position allowing seed from said second pickup unit to be delivered to said seed tube for planting while collecting seed from the first finger pickup unit; and programmable control means for controlling the timing of shifting of said top valve and said bottom valve.
Preferably the plot planter includes a linear actuator to move said sliding block between the first block position and the second block position. The linear actuator is powered with one of fluid or mechanical power.
Preferably, said first finger pickup unit communicates with said first seed chamber through a first loading tube and said second finger pickup unit communicates with said second seed chamber through a second loading tube.
The top valve, first and second finger pickup units and bottom valve are preferably each mounted onto a tubular frame.
The first finger pickup unit and second finger pickup unit are each preferably provided with a plate member to reduce the volume within said pickup units whereby increasing the likelihood that the last seeds remaining in the finger pickup units will be planted.
The first finger pickup unit and said second finger pickup unit are preferably both driven by a common drive.
A linear actuator is also preferably provided to move said bottom valve between the first position and the second position, which can also be powered with fluid or mechanical power. The programmable control means preferably further comprises a programmable relay having a sensor to count pulses generated from an encoder wheel. The first finger pickup unit and said second finger pickup unit are preferably turned by a seed shaft and said encoder wheel is mounted on said seed shaft. The encoder wheel has a plurality of pins on a face thereof and the pins are timed with the distance that said plot planter travels whereby when the sensor counts a predetermined number of pins the plot planter will have moved a known fixed distance and said relay will shift the top valve and bottom valve to cause seed of a different kind to be planted thereafter. Preferably, the top valve is shifted first and after a few more counts the bottom valve is shifted.
The relay can preferably be reset to begin counting pins again by actuating a simple switch controlled by an operator of the plot planter. In the preferred embodiment of the invention, the encoder wheel has 24 pins thereon and said planter travels {fraction (1/24)}th of a revolution of said encoder wheel when said planter travels 2.5 inches.
The programmable control means can be programmed to precisely control the spacing between individual seeds of a first seed type being planted and the length of a row of a said first seed type before the top valve and bottom valve are shifted to plant a second seed type.
Preferably, the second valve further comprises a container to collect excess seeds from the first finger pickup unit and the second finger pickup unit when such seed are being collected and not planted. Such container is preferably of sufficient volume to hold several seed from several plots with excess seeds.
A funnel is preferably provided to facilitate loading of seeds into said first seed chamber and said second seed chamber.